1. Field of the Invention
The subject of this invention relates to an improved electrical contact, and more particularly to an electrical contact for use in high vibration environments where it is advantageous to provide secondary locking.
2. Description of the Prior Art
The are many applications for electrical connectors where the interconnection is subject to high vibrations, for example automotive electrical systems. Furthermore, it is desirable to minimize the size of the electrical contact to provide for a high density of electrical connections. As the size of the electrical contact is reduced, the magnitude of the mechanical forces that can be exerted at the electrical interconnection is also reduced. As a result, in high vibration environments, the magnitude of the mechanical force may not be sufficient to retain engagement between the electrical contact and the mating component to maintain the electrical interconnection.
One interconnection commonly used in high vibration environments is between a tab-type terminal and a socket-type electrical contact which is retained in a connector housing that is adapted to mate with the component containing the tab-type terminal. A known socket-type electrical contact includes two opposing contact arms that are constricted to engage the tab-type terminal therebetween and exert a normal force against the tab. The contact arms are interconnected to a central body that commonly formed into a box like member. A transition section extends from the central body opposite the contact arms to a conductor engaging portion that may be adapted to the crimpably attached to a conductor, such as an insulated wire.
In order to assure the interconnection of a socket-type electrical contact as described above, it is known to include a secondary locking feature that mechanically locks the electrical contact to the housing within which it is disposed. The secondary locking member is typically a non-conductive component which may, or may not, be integrally formed as part of the connector housing and includes a bearing surface, or an engaging surface, that blocks the contact to prevent displacement thereof. The contact must contain a complementary bearing surface that is engageable or abuttable by the secondary locking member so that movement of the contact may be opposed. It is known to include this bearing surface as windows within the box-like central member, as a notch formed within the transition section of the contact, or to use the back edges of the box.
A problem with all of these constructions is that the bearing surface of the contact engageable by the secondary locking member is limited to the thickness of the material from which the contact is formed. This thickness is constantly being reduced. Another problem is that these bearing surfaces typically have sharp edges from the stamping and forming processes that are typically used to manufacture the contact which could, as a result of the vibration, result in the degradation of the secondary locking member, which is typically plastic, sufficient to enable the displacement of the socket relative the tab. This displacement may ultimately lead to the failure of the electrical interconnection.